But they should have known, you can actually see the ice on the road in the video. Plus weather reports with advance warning. Plus freezing temps plus rain = ice no matter where you live. And since this is apparently a bridge, bridges are well known for freezing early and often. In cold weather states bridges often are(I’m blanking on the word) hashmarked or roughened to prevent this. Many also have deicers built into the bridge. Not that Texas would have anything like that.
This is just totally wrong as shown by the tens of millions of drivers that drive on ice for months at a time. Every time the temp hangs around freezing you get this especially at intersections.
When it comes to winter driving, my sister, who lives near Bozeman MT, swears by a Toyo that has crushed walnut shells in the rubber. They are not studded, in the traditional sense, but the shell fragments provide comparable traction. Of course, she has been driving in adverse Montana weather for the better part of five decades: being familiar with dicey conditions makes a huge difference.
Named after the tule grass wetlands (tulles) found in the area, the Tule Fog is a radiation fog caused by the combination of a high relative humidity (typically after a heavy rain), calm winds, and rapid cooling during the night. The fog develops on cold winter nights when the ground is moist from recent rain.
Well, I’m not disagreeing with you about whether they were going too fast. Not at all. However, I do think that in these circumstances, it can be understood why they tragically didn’t realize this.
700 feet is a long distance, but it’s unlikely the first wreck happened at the peak of the next rise, it’s just as likely to have happened at the midpoint, so now we’re looking at 350 feet between when it’s revealed to you that you have to stop as soon as possible, or you’re plowing into something. A completely loaded semi’s likely to have a problem doing that in snow from 60, on ice it’s probably not happening at all.
But these folks had been driving on a freeway that had been damp, but not actually frozen for some time, and probably most of the roads they had seen were actually dry. The conditions were out there, but the hadn’t seen the combination necessary to actually coat the road with ice. If they were (as is often a common behavior in Texas) sprinting between everything they can identify as a bridge, and slowing down to a crawl across them: they’re crazy, and this situation was going to sneak up on them, but they’re probably in the majority. There was another 26 car pileup in Dallas that morning, but most of the roads were passable, and I was able to run several errands without seeing anything but a couple of patches of ice.
However, I do slow the hell way down when ice is even a possibility, but I’m also aware that when I’m too cautious, I’m a traffic hazard. So I probably would have been one of the persons with probably only a fender-bender until hell came raining down in that situation. I wouldn’t absolve the persons who were driving too fast of criminal or civil culpability, but how they got there is understandable. Hopefully we can figure out how to combat that mindset by understanding it.
Well, I heard them complain in a news conference that they were having problems even moving around the accident site due to the ice and had to treat the area themselves, and a report that stated they needed to use their own sand/salt to safely access the area. I may be misunderstanding the second statement.
And the NTTA is officially a not-for profit set up by the state:
I’m not sure if that insulates the state from having to make sure that stretch of freeway is treated or not. I’m still not terribly fond of the NTTA basically creating what seems to be a plan for a two-tiered system of commuting where you gain less traffic, and therefore more safety and less time consumed because you pay more taxes per mile. Yes, I do use them, but I’d prefer they were like the original DFW turnpike that got paid off early and just became the stretch of I-30 between Dallas and Fort Worth when they removed the booths (yeah, it’s getting new NTTA express lanes now…mumble, mumble).
60 mph = 88 feet per second…if the hazard is 350 feet ahead, that would leave a mere 4 seconds total to notice the situation, decide that it’s serious, apply the brakes, etc. When one driver fails the test, the situation would escalate quickly.
My hunch is that traffic was flying along on the treated part, not a care in the world. If that was express the were going faster than 60 mph. They hit ice, tried the brakes, but to borrow a line from “Apollo 13” Sir Isaac Newton was in the driver’s seat.
It will be interesting to see what comes to light in the next few days or weeks. I saw a statement like that (it may have been the same one) and thought, ‘They hadn’t treated it. Rescuers were slipping too.’
However I guess we should allow for the possibility that it was treated and accidents happened, BUT between the time rescue was notified and got there, additional precip fell and froze. My WAG is that in colder areas of the country, road crews don’t think “One and done.” They probably read conditions throughout the day and adjust, or maybe they know from experience to salt before each rush hou, or whatever. That particular stretch looks like it would be more vulnerable, given the “Bridges may ice before road” thing, requiring more attention.
To add to that excellent description, besides being one of the weirdest damned things you’ll see on occasion (I had family I’d visit in Fresno during the winter), the Central Valley is a very large agricultural area. Agricultural areas at that time, maybe still do, get rid of a lot of waste through burning. Burning creates soot and smoke, and both can be great sites for water droplets to condense upon.
The net effect is some truly ridiculously thick fog. Rising from the ground up, versus the sky down. Not that it stops idiots from continuing to go fast on 99. I don’t get it. I’ve been reduced to 30-40 in the right lane, blinkers on, because you just couldn’t see any further down the road. And people would still do 65+ going past you. At night, in fog.
Haven’t driven in those conditions in years. Now, I’d stay home. Then? The ski slope in the Sierras was opening at 8 on Thursday morning, and damnit, I was going to be there.
Excuse my very noob question, but doesn’t salt work on black ice? If it does, then the highway simply wasn’t prepared the way it should have been for the prevailing conditions. Also why weren’t emergency speed limits imposed if the conditions were so dire? I get it that Texas doesn’t get much snow but it doesn’t require a PhD to know conditions are dangerous.
There is one small problem with salt. At 20F (I think that is what they were saying), the black ice is essentially dry. You throw salt on it, you have salt lying upon ice. Nothing actually happens until the top of the ice warms up enough to form a moisture layer into which the salt will dissolve.
In my area, which rarely gets below the mid 20s, they use a liquid spray. Which TxDoT probably should have done, had they been on the ball. Or they could have blocked the express lane off and had some sort of slow-down road-block like setup. But they were not on the ball, and Texas drivers are not notorious for liking to be told how to drive (or much or anything else).
TxDoT does use a magnesium chloride spray. That’s why I kind of think either this stretch had been missed or had been treated early in the process and had already mostly been beaten off the road.
Well, that would have required them to have the foresight to shut it down before it actually froze up. I’ve never seen TxDoT preemptively close a road.
It does. I’m from Chicago-ish, and if they didn’t salt the roads here, we’d all be screwed. The first snow or freeze of the season generally features lots of spinouts and cars off of the road. (Hell, there was an abandoned car in a ditch on my way to the grocery store this morning. Ahem, Indiana plates.)
While true in principle, this only happens when temperatures are much, much lower than 20F, typically closer to 0F. Otherwise all ice contains a minuscule film of water over it that is constantly interacting with the ice below – it only takes a few molecules for the salt to begin to act and start a chain reaction. And even if it didn’t, the pressure of anything rolling or walking over ice lowers the melting point and allows that to happen. If this was not so, ice wouldn’t be slippery to begin with. I speak as someone who has often spread salt over apparently “dry” icy porches, steps, and sidewalks in very cold weather and watched it start to take effect immediately.
Once I was traveling on I-5 before sunrise and the tule fog had lifted – about eight feet. It was eerie, like driving in a covered parking lot with a low roof but there were no support pillars.
You are correct, but it’s not much of a difference for this part of the discussion other than NTTA is funded separately from the tolls it generates. It’s still a nonprofit set up by the state, and both use MD 20 for de-icing.
I salt my sidewalks and sometimes driveway all the time in the winter. It’s been -25F to -30F every night for a week. Daytime highs are -10F to -15F and salt works just fine, even without anyone walking or driving over it.
Just a point to how weather effects areas differently. Where I am it’s been below zero for over a week and everything is running covid normal, but my SIL called today from Austin, Tx. and they have pushed back her covid vaccine shot back to a week from next Friday and grocery stores are closing at 7pm. The reason? It’s too cold at +25F.
Tule fog hasn’t been a thing in quite a while. The last couple of years, we’ve had a few mornings of brief >50 yd. visibility. Compare that to all day fog of less than 25 yds. Yet even then, idiots would drive full speed and pass on single lane roads. No headlights, those are for sissies.